619 research outputs found

    Tocopherols and phytosterols concentration from vegetable oil deodorized distillater through molecular distillation process

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    Orientadores: Maria Regina Wolf Maciel, Cesar Benedito BatistellaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: Resumo: Os tocoferóis e fitoesteróis são componentes minoritários presentes em plantas e óleos vegetais. Os tocoferóis apresentam atividades vitamínicas e propriedades antioxidantes. A vitamina E é composta por 4 tocoferóis (a, b, g e d) e 4 tocotrienóis (a, b, g e d). Os fitoesteróis possuem propriedades anticolesterolêmica e anticarcinogênicas. Uma das principais fontes de tocoferóis e fitoesteróis são os destilados desodorizados de óleos vegetais. Os destilados desodorizados são constituídos de ácidos graxos, triglicerídeos, fitoesteróis, hidrocarbonetos, aldeídos, cetonas, tocoferóis, dentre outros. Neste trabalho foram estudados dois tipos de destiladores moleculares: centrífugo e de filme descendente (agitado). Os destilados desodorizados de óleo de soja, canola e girassol foram processados no destilador molecular de filme descendente. A recuperação de ácidos graxos livres em função da razão entre as vazões das correntes de destilado e de resíduo apresentou o mesmo perfil para os três destilados desodorizados estudados. O destilado desodorizado de óleo de soja, abundante no Brasil, foi processado no destilador molecular centrífugo. O processo de destilação centrífugo foi estudado tanto experimentalmente quanto por simulação. Foi realizado um planejamento fatorial visando analisar o comportamento das variáveis (temperatura do evaporador e vazão de (alimentação). Observou-se que ocorre uma maior eliminação de ácidos graxos livres a altas temperaturas do evaporador e baixas vazões de alimentação. Tanto o processo de destilação molecular de filme descendente quanto o centrífugo duplicaram a concentração inicial de tocoferóis. Através do processo de destilações sucessivas triplicou-se a concentração de tocoferóis e, com destilações sucessivas seguidas de uma etapa de cristalização, quaduplicou-se a concentração de tocoferóis em relação à concentração originalAbstract: Tocopherols and phytosterols are minority compounds present in vegetables oils. Tocopherols show vitaminic activities and antioxidant properties. Vitamin E is composed by four tocopherols (a, b, g and d) and four tocotrienols (a, b, g and d). The phytosterols have anticholesterolemic and anticarcinogenic properties. The main natural sources of tocopherols and phytosterols are the vegetable oil deodorized distillate (VODD). The deodorized distillates are composed by fatty acids, acylglycerols, sterols, hydrocarbons, aldehydes, ketones and tocopherols. In this work, two kinds of molecular distillation equipments were studied: centrifugal and falling film (wiped). The soybean, canola and sunflower oil deodorized distillates were carried out at falling film molecular distilator. The free fatty acids recovery in function of the Distillation mass/Residue mass ratio shows similar behavior to the three VODDs. Soybean oil deodorized distillate, abundant in Brazil, was chosen to be processed in the centrifugal molecular distiller. This centrifugal molecular distillation process was studied experimental and simulated. The factorial design was carried out to analyze the variable behavior (evaporator temperature and feed flow rate). The free fatty acids elimination occurs at higher evaporator temperatures and lower feed flow rate. The falling film and centrifugal molecular distillation process duplicates the tocopherol concentration. Through successive distillations, the tocopherol concentration was three times higher and with the crystallization, the tocopherol concentration was four times in relation to the original concentrationDoutoradoDesenvolvimento de Processos QuímicosDoutor em Engenharia Químic

    Otimização de colunas de destilação complexas

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    Orientador : Maria Regina Wolf MacielDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: Misturas binárias com comportamento ideal e não ideal são estudadas nesta dissertação. O processo de destilação convencional é estudado para misturas binárias e ternárias ideais. As misturas n-hexano/n-heptano e n-hexano/n-heptano/n-octano foram estudadas. Dois processos de separação são estudados e comparados para a mistura binária não-ideal: destilações azeotrópicas homogênea e heterogênea, as quais apresentam diferentes comportamentos dinâmicos. A mistura etanol/água é considerada para este estudo visando otimização de variáveis para a minimização de energia consumida no processo. Novas alternativas de processo foram estudadas, sob o ponto de vista da substituição de solventes e de projeto. As considerações de substituição do solvente etileno glicol, usado na destilação azeotrópica homogênea e do benzeno, usado na destilação heterogênea, são extremamente importantes do ponto de vista de minimização de geração de poluentes. Estudos de comportamentos dinâmicos dos sistemas foram feitos para os três processos de destilação estudados. Foram perturbadas positiva e negativamente a vazão de alimentação, a vazão de solvente, a composição da corrente de alimentação e a carga térmica do refervedor. Os sistemas ideais apresentaram respostas semelhantes qualitativamente frente às perturbações. Para os sistemas não ideais, as perturbações podem acarretar diminuição na pureza dos produtos, a energia no refervedor pode não ser suficiente para vaporizar a alimentação excedente, podem diminuir a temperatura na base da coluna de destilação. Um comportamento oposto pode ser obtido ao se perturbar a coluna em outra direçãoAbstract: Binary mixtures presenting ideal and non ideal behaviors are studied in this work. The process of conventional distillation is studied for binary and ternary ideal mixtures. The n-hexane/n-heptane and n-hexane/n-heptane/n-octane mixtures were studied. Two processes of separation are studied and compared for the binary non-ideal mixture: azeotropic homogeneous and heterogeneous distillations, which present different dynamic behaviors. The mixture ethanol/water is considered for a study of optimization of many variables to minimize the energy consumed in the process. New alternatives of process were studied, from the point of view of the substitution of solvent. The considerations of substitution of the solvent ethylene glycol, used in the homogeneous azeotropic distillation and of benzene, used in the heterogeneous distillation, are extremely important from the point of view of minimization of generation of pollutants. Studies of dynamic behaviors of the systems were made for the three distillation processes. Positive and negative perturbations were generated in the feed flow, the solvent flow, the composition of feed flow and the heat flow of reboiler. The ideal systems presented similar responses qualitatively front to the disturbances. For the non ideal systems, the disturbances can cause reduction of the products purity, the energy in the reboiler may not be enough to vaporize the exceeding feed, they can also decrease the temperature in the bottom of the column. An opposing behavior can be obtained if the disturbance happens in another directionMestradoDesenvolvimento de Processos QuímicosMestre em Engenharia Químic

    Epithelial Wnt Ligand Secretion Is Required for Adult Hair Follicle Growth and Regeneration

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    β-Catenin, a key transducer molecule of Wnt signaling, is required for adult hair follicle growth and regeneration. However, the cellular source of Wnt ligands required for Wnt/β-catenin activation during anagen induction is unknown. In this study, we genetically deleted Wntless (Wls), a gene required for Wnt ligand secretion by Wnt-producing cells, specifically in the hair follicle epithelium during telogen phase. We show that epithelial Wnt ligands are required for anagen, as loss of Wls in the follicular epithelium resulted in a profound hair cycle arrest. Both the follicular epithelium and dermal papilla showed markedly decreased Wnt/β-catenin signaling during anagen induction compared with control hair follicles. Surprisingly, hair follicle stem cells that are responsible for hair regeneration maintained expression of stem cell markers but exhibited significantly reduced proliferation. Finally, we demonstrate that epidermal Wnt ligands are critical for adult wound-induced de novo hair formation. Collectively, these data show that Wnt ligands secreted by the hair follicle epithelium are required for adult hair follicle regeneration and provide new insight into potential cellular targets for the treatment of hair disorders such as alopecia

    Class Practice Research Aimed at Achieving Proactive, Interactive, and Deep Learning in the Junior High School Music Department: From the Perspective of Teaching Methods in Instrumental Ensemble

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    The purpose of this study was to clarify which teaching method could produce proactive, interactive, and deep learning, during an instrumental ensemble, and to assess the results of implementing such a program. We developed and presented the instrumental ensemble class plan based on the bottom up instruction method at two junior high schools. Data were collected by using a questionnaire and an M-GTA. We found that each student displayed a proactive learning attitude toward the music while maintaining an awareness of their own development areas and growth. Furthermore, the students showed an interactive learning attitude during collaborative activities by watching and listening to others while observing their performance in an effort to improve the quality of music , and learn through the class experience. In addition, we noticed an attitude that promoted deep learning whereby students attempted to solve problems and create music while utilizing what they learned from negative experiences. In addition, the bottom up instruction approach used during instrumental ensemble training was associated with originality, growth and the acceptance and awareness of others

    Social cost of mining-related lead (Pb) pollution in Kabwe, Zambia, and potential remediation measures

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    Lead (Pb) pollution has been one of the major environmental problems of worldwide significance. It is a latent factor for several fatal illnesses, whereas the exposure to lead in early childhood causes a lifetime IQ loss. The social cost is the concept to aggregate various adverse effects in a single monetary unit, which is useful in describing the pollution problem and provides foundation for the design of interventions. However, the assessment of the social cost is scarce for developing countries. In this study, we focus on the lead pollution problem of a former mining town, Kabwe, Zambia, where mining wastes abandoned near residential areas has caused a critical pollution problem. We first investigated the social cost of lead pollution that future generations born in 2025–2049 would incur in their lifetime. As the channels of the social cost, we considered the lost income from the IQ loss and the lost lives from lead-related mortality. The results showed that the social cost would amount to 224–593 million USD (discounted to the present value). Our results can be considered conservative, lower bound estimates because we focused only on well-identified effects of lead, but the social cost was still substantial. Then we examined several engineering remediation measures. The results showed that the social cost can be reduced (the benefits of remediations) more than the costs of implementing remediation measures. This study is the first to investigate the social cost of mining-related lead pollution problem in developing countries. Our interdisciplinary approach utilises the micro-level economic, health and pollution data and integrates the techniques in economics, toxicology and engineering.publishedVersio

    Common Teaching Materials in Japanese School Music Education: The Moldau in Junior High Schools

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    Common teaching materials for singing, which are particular songs for generations set by the Ministry of Education in Japan, have been employed for the curriculum guideline. Since 1998, common teaching materials for appraising, which are particular pieces of music set by ministry of education, have not employed for the curriculum guideline. This change came about as a result of fewer music lessons being provided in Japanese schools; it was not because there was any question over the essential significance of the common teaching materials presented. We reviewed the significance of common teaching materials in a previous study. There, we examined how the Fate motif in Beethoven’s Fifth Symphony was dealt with in textbooks and teacher manuals. In the present study, we examined The Moldau by Smetana in the same way

    Genome-wide analysis of mechanosensitive channel of small conductance (MscS)-like gene family in common bean

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    Mechanosensitive (MS) ion channels are transmembrane proteins that open and close in response to mechanical forces produced by osmotic pressure, sound, touch and gravity. In plants, MS have an important role in different biological processes like gravity detection, maintenance of plastid shape and size, lateral root emergence, growth of pollen tube, and plant-pathogen interactions. In this study, homologous mechanosensitive channel of small conductance (MscS)-like gene family in common bean was identified. Nine Phaseolus vulgaris MscS-like (PvMSL) genes were found to be distributed on five chromosomes. A complete overview of PvMSL genes in common bean is presented, including gene structures, chromosome locations, phylogeny, protein motifs and expression pattern. Subcellular localization predictions of PvMSL family revealed their location to plasma and chloroplast membrane. Phylogenetic analysis of nine PvMSL proteins resulted in two main classes. The predicted gene structure, conserved motif, domain and presence of transmembrane regions in each PvMSL strongly supported their identity as members of MscS-like gene family. Four duplicate events of PvMSL genes were discovered in P. vulgaris chromosomes, and tandem and segmental duplication may cause the expansion of PvMSL genes. Furthermore, PvMSL genes displayed differential expression patterns in tissues and organs. This is the first step towards genome-wide analyses of MSL genes in common bean. Thus, the data obtained in this study provide resources to select candidate genes for future functional analyses that will help understand plant growth, development, and function of MSL gene family in P. vulgaris.Key words: Mechanosensitive, phylogenetic analysis, gene duplication, plant, in silico

    Research on Proactive, Interactive, and Deep Learning in Junior High School Music Department: Focusing on the Thinking Process of the Four Extracted Students in Instrumental Ensemble

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    We investigate the thinking processes of four extracted students as they provide bottom-up-based instructions to achieve proactive, interactive, and deep learning in instrumental ensembles. In addition, we analyze the reflections of the extracted students using SCAT to clarify how they are transforming their thinking and create diagrams to delineate their learning processes. The results showed that the four participants shared the following features. First, they were performing self-regulated learning and searching for the practice method and way of thinking that they needed in frustration, failure, and task awareness. Second, they were able to develop their own awareness (their role, mission in the instrumental ensemble, and so on) through problem-solving and collaborative learning. Third, the significance of instrumental ensemble was considered through problem-solving while using past learning and creating musical expressions. From these results, the bottom-up-based teaching method in instrumental ensemble can be deemed to have the effect of promoting student’s proactive, interactive, and deep learning
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